Letters.

Infertility and Endometriosis

I read with interest the opposing views of Dr. Thomas M. D'Hooghe and Dr. Craig A. Witz on the association between minimal or mild endometriosis and infertility ("Pro & Con: Does minimal or mild endometriosis cause infertility?" May 1, 2002, p. 5).

Spontaneous monthly fecundity rates in endometriosis are 4%-6%, according to Dr. D'Hooghe. They were only 2.4% in the Canadian Endocan study and lower than that in other reports. Dr. Witz correctly indicated that after resection of endometriosis, the pregnancy rate in the Endo can study "was only modestly increased."

Indeed, when the pregnancy rate after surgical or medical treatment of endometriosis--even though it is frequently said to have doubled--is evaluated using life-table analysis and expressed as the monthly fecundity rate, it increased from 5.5% to 6.5%. Those rates are much below the rate of age-matched controls.

What was not clearly stated by either discussant is that controlled ovarian hyperstimulation/artificial insemination with the husband's sperm in stage I-II endometriosis results in 11%-15% cycle fecundity and that with in vitro fertilization, cycle fecundity at the leading centers is as high as 47% and above.

These numbers are easy to compare and can be easily applied to the decision-making process. They clearly indicate that ovulatory dysfunction, problems with gamete/embryo transport, and the adverse effect of the intraperitoneal environment on different reproductive functions are the factors that cause infertility in women with minimal or mild endometriosis.

W. Paul Dmowski, M.D.